class: inverse, middle, left background-image: url(data:image/png;base64,#laseminverse.png) background-position:5% 95% background-size: 50% ## Hip rotation strength after anterior cruciate ligament injury: relationship to functional, symptomatic and structural outcomes **Michael Girdwood**, Adam Culvenor, Brooke Patterson, Ali Guermazi, Kay Crossley m.girdwood@latrobe.edu.au --- ## Why the hip after ACL Reconstruction? .pull-left[ #### What we know: - 24% of people suffer from patellofemoral pain at 1 year post ACLR .font60[(Culvenor, 2017)] - Hip muscle weakness is characteristic of PFJ pain and knee osteoarthritis .font60[(Rathleff, 2014)] - Hip rotation muscles play a role in the control of knee positioning during movement .font60[(Cashman, 2012)] ] .pull-right[ #### What we **don't** know: - Limited research into hip rotation strength after ACLR - Whether hip rotation strength is associated with long term knee sypmtoms ] --- class: inverse, middle ## Research Question: > - How does hip strength differ between the injured and non-injured side in people 1-year after ACLR? > > - Is hip strength associated with functional, symptomatic and structural outcomes? --- ## Methods: participants .pull-left[ - Longitudinal study monitoring knee joint structure, function and symptoms (Culvenor et al, 2015) - Primary ACLR (HS autograft) 1 year prior - No structured rehab ] .pull-right[ | Measure | ACLR Group (n=111) | |---------|--------------------| |Age (years) |27.4 (22.2 - 36.1) |Gender (n, % F)| 43 (35%) |Height (cm)| 175 (170 - 181) |Weight (kg) |81.2 (67.0 - 90.8) |BMI (kg/m2)| 25.6 (23.2 - 27.8) |Tegner Activity | 6 (4 - 7) .center[.font60[Median (Interquartile Range (IQR)) ]] ] <br></br> .center[<img src = "data:image/png;base64,#koala.png", width = "30%" /> ] --- ## Methods .center[ **Hip External Rotation & Internal Rotation with HHD** <img src = "data:image/png;base64,#hipstrength.png" width = "70%" /> ] .right[Measured *only at 1 year*] --- ## Methods: Outcomes and Analysis .m[<img src="data:image/png;base64,#DAGSMA.png" />] --- ### Results: Injured vs non-injured side .left-column[.black[#### Controlling for gender: Small but significant difference in ER strength SMD = -0.33 (-0.6 to -0.07)] <br></br> .black[No difference in IR strength.]] .right-column[<img src= "data:image/png;base64,#affnonaff.png" width = "85%" />] --- ## Assocation to .green[Function] - Both Hip ER and IR were associated with all measures at 1 year and 5 years. - Strongest relationships with <u>Hop for Distance</u> and <u>Triple Crossover Hop</u> for both. - Adjusted R² values were lower at 5 years: <br><br/> .pull-left[ | .purple[1 Year] | ER | IR | |-|---|---| |Hop for distance| 0.51| 0.47 | One leg rise | 0.24 | 0.21| | Side Hop | 0.5 | 0.34 | | Triple Hop | 0.6 | 0.59 | ] | .green[5 Year] | ER | IR | |-|---|---| |Hop for distance| 0.4| 0.33 | One leg rise | 0.22 | 0.15| | Side Hop | 0.42 | 0.31 | | Triple Hop | 0.46 | 0.38 | .center[.font90[(age and gender included in models)]] --- ## Association to .blue[Symptoms] - .font90[**Higher** hip ER & IR strength was associated with **superior** AKPS at 1 and 5 years.] .center[<img src = "data:image/png;base64,#ameplot.png" width = "107%"/>] --- ## Assocation to .red[Structure] (Imaging) .pull-left[ - Lower hip ER strength was associated with **worsening tibio-femoral** cartilage lesion score **.black[at 5 years]** - Odds Ratio: 0.01 (95%CI 0.00 to 0.41) - No other significant relationships identified ] .pull-right[<img src = "data:image/png;base64,#kneemri.png" width = "80%" /> ] --- ## Discussion - Hip ER may influence symptomatic and structural outcomes as it is critical to single leg functional tasks. - ER specific weakness could result from: - lack of training/rehab - weakness broadly of the entire lower limb (not specific to the hip). .center[ <img src = "data:image/png;base64,#deadlift.jpeg" width = "50%" /> ] --- class: middle ## Key Summary .content-box[ - Hip ER strength was impaired on the injured side at 1 year post ACLR - This may contribute to functional, symptomatic, and structural outcomes up to 5 years post-operatively. - Contrary to initial hypothesis, hip rotation strength was not associated with PFJ structure ] --- class: inverse, middle background-image: url(data:image/png;base64,#laseminverse.png) background-position:5% 95% background-size: 50% .center[<img src = "data:image/png;base64,#koalateam.png" width = 80%/>] ## Thank you! .right[####Questions: m.girdwood@latrobe.edu.au @m_girdwood]